Saturday, June 06, 2009

Gold in its pure form is yellow in color and is called PURE GOLD or FINE GOLD. Its purity represented in KARAT.

WHY IS GOLD ALLOYED: It is alloyed or mixed with other metals in a consistent blend for the following most important reasons:

To achieve the strength or stability in gold

Pure gold is very soft and jewelry made in this kind can easily bend and get misshaped. Fine work such as filigree is usually not recommended in pure gold because it can bend out of shape to irreparable extents fairly easily

Stones set in pure gold can easily fall out because of the softness of the metal holding them. Most commonly plain gold jewelry is made in 22 K in India and 14K or 18 K in the US.

To make a product in higher karat gold, the thickness of the product has to be considerably increased to increase its stability. Thus you will land up paying more for the same design made in higher karat gold.

To achieve color in gold

Gold in its purest form is yellow. Gold is often alloyed with other metals such as silver, copper, zinc, palladium etc to achieve a whiter or paler look. “White” gold is an extremely pale color of gold which looks almost white. This is usually created in 18 K gold or lesser purity of gold.

Normally the bright yellow of pure gold reflects off beautifully on darker skin tones. This makes 22 K yellow gold a popular choice in India as well as Africa. However, pale yellow colored jewelry looks beautiful on most paler or lighter colored skins and hence becomes a popular metal in the US, Italy and Australia. White gold is now a popular choice all over the world due to its publicity and resemblance to platinum.

Other colors in gold are pink gold, purple, black, green and white. These colors depending on the properties of each are used to enhance design without compensating on the value of the product.

Workability increases when the gold is alloyed

It is simpler to create solder (material used to join two pieces of gold) for a lower karat of gold rather than struggle with achieving the purity of 24 K gold.

For a craftsman it is easier to work on lower Karat of gold most of the time if the product has to be hand crafted. He has to be much more attentive so as not to ruin his work when working with fine gold.

For these above reasons, the making or labor charges may be lesser for a lower karat product in gold.

The cost of metal in a product is reduced considerably

If in a 18K gold product, the value of metal used is $ 750, then the same design made in 24K gold will be $ 1000. The same design in 9K gold will be $ 375 only. Thus in a fixed budget one can get more if they are willing to compensate on the karat value of the metal.

Since the weight of gold is more than that of silver or copper, (which is the most common alloying metal for making jewelry) hence the mass of 10gm pure gold will be lesser than that of 9 K gold.

This means that a 10 gm gold bangle in 24 K is smaller to look at than the same design same weight in 9 K gold.

Due to its softness, the higher the karat of gold, the faster it gets scratches thus requires more frequent polishing and hence the loss of precious material. This wear and tear makes the product look older sooner.

ABOUT THE ALLOYS

Pure or fine gold is 24 K and theoretically this means that the metal has 100% gold content in it.But for making jewelry, an example of 18 K gold in terms of “fineness” is the gold content expressed in 750 parts per thousand (75.0% gold). The remaining 25% of the metals in this alloy can vary depending upon the property desired.

The percentage of gold in various alloys is given below (the commonly used Karat values are marked in bold).

24 K = 24/24 * 100 = 100 % Gold; no other metal

23 K = 23/24 * 100 = 95.83 % Gold; 4.17 % other metals

22 K = 22/24 * 100 = 91.66 % Gold; 8.34 % other metals

21 K = 21/24 * 100 = 87.5 % Gold; 12.5 % other metals

20 K = 20/24 * 100 = 83.33 % Gold; 16.67 % other metals

19 K = 19/24 * 100 = 79.16 % Gold; 20.84 % other metals

18 K = 18/24 * 100 = 75 % Gold; 25 % other metals

17 K = 17/24 * 100 = 70.83 % Gold; 29.17 % other metals

16 K = 16/24 * 100 = 66.66 % Gold; 33.34 % other metals

15 K = 15/24 * 100 = 62.5 % Gold; 37.5 % other metals

14 K = 14/24 * 100 = 58.33 % Gold; 41.67 % other metals

13 K = 13/24 * 100 = 54.16 % Gold; 45.84 % other metals

12 K = 12/24 * 100 = 50 % Gold; 50 % other metals

11 K = 11/24 * 100 = 45.83 % Gold; 54.17 % other metals

10 K = 10/24 * 100 = 41.66 % Gold; 58.34 % other metals

9 K = 9/24 * 100 = 37.5 % Gold; 62.5 % other metals

8 K = 8/24 * 100 = 33.33 % Gold; 66.67 % other metals

Most jewelry worldwide is marked with the caratage or fineness. This may be part of a Hallmark on the jewelry. To read more about Hallmarking and Assaying of gold, please click here.

Something very interesting about gold alloys is that with varying quantity or percentage of alloying metals used, the physical and chemical properties of that alloy can be very cleverly manipulated. A very common use of this fact is that 18 K white gold and 18 K yellow gold has the same content of gold in them, but the color changes. 18 K pink gold is harder to work with than 18 K yellow gold. To read about these differences and how one can use these in their jewelry, click here.

Friday, June 05, 2009

One of the most simplified yet complete informative articles about diamond origins, history, mining and distribution, industry, synthetic diamonds and jewelry is available on the website of American Museum of Natural History.

A must read is the mining and distribution section. I have never come across a more comprehensive writeup about the behind the scenes life of a diamond.

The most important thing about Tiffany diamonds is the cut. This is the most neglected 4th C of a diamond which Tiffany pays special interest to. It is interesting to note how a paler colored, lower clarity diamond will also start shining brilliantly when cut within the ideal proportion limits of a standard round brilliant cut.

Costco carries everything of high standards but in case of diamonds, they definitely do not go for the 'highest' standards of cut. I am not sure about the diamonds that were compared from Tiffany and Costco in the mentioned article, but so far, I have not come across a Costco diamond which falls in the 'excellent' or 'ideal' or 'signature ideal' cut category. Tiffany does.. all their diamonds whether they are F color or D, Internally flawless or very slightly included, small or big are in the very least ideal cuts adhering to the standard round brilliant cuts.

The article that got me to question my research and come back to my original assessment of Costco vs Tiffany diamonds: Tiffany's Bling vs. Costco's

And YES, the prices will differ a LOT when the cut grade changes. You can go through the change in price by simply comparing diamonds on bluenile.com then costco.com and eventually Tiffany.com

Tiffany diamonds are as I already recommended top of the line amazing, but at the end of the day, so some diamonds, you are paying over 50 % more than the actual value of the material that goes into your jewel... that is the cost of the "brand" and all the benefits that you get along with it. It is completely up to you from this point onwards whether or not you want to pay that price for the "label".

For any questions suggestions, comments or advise on buying diamonds keep visiting my website at www.jewelsutra.com or write to me at surbhi@jewelsutra.com .